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A Veteran Soldier must be equipped with Guns to function as a Soldier.
Civilopedia[]
Veteran Soldiers are hardened warriors, educated on the field of battle in the ways of war. And by the 17th century, there was more than enough "education" going on in Europe to train the budding soldier. Dozens of conflicts, including the Thirty Years' War and the Eighty Years' War, ravaged Europe in this century, making the availability of fresh training for green soldiers an easily-accessed commodity.